Fig. 7

SF3B3 knockdown and mTOR inhibitor induce synergistic antitumor activity. A Representative western blots of LC3 and SQSTM1/p62 in SF3B3-knockdown CRC cells. LoVo and HT29 cells were treated with siRNAs for 72 h. B Representative autophagic flux images. mCherry-GFP-LC3B labeled CRC cells were transfected with SF3B3 siRNAs for 48 h. C Representative transmission electron microscopy images presenting the ultrastructure of the SF3B3-knockdown CRC cells. Arrows indicate autophagic vacuoles. LoVo and HT29 cells were treated with siRNAs (siSF3B3#1 + siSF3B3#2) for 72 h. Scale bars, 1 µm. D Schematic diagram of two PDX models. PDX1 models were treated Lentivirus-shNC vs Lentivirus-shSF3B3#1, and PDX2 models were treated Lentivirus-shNC vs Lentivirus-shSF3B3#2. E Tumor growth, tumor weights, and tumor photos of two PDX mouse models after intratumor injection of shNC or shSF3B3 lentivirus. F Representative IHC images of SF3B3 and Ki67 in two PDX tumor tissues. G Representative western blots of lipogenesis-, autophagy- and apoptosis-related proteins in PDX tumor tissues. H Representative images of patient-derived CRC tumor organoids after treatment with SF3B3 shRNA lentivirus and everolimus. Digested organoids were transduced with shSF3B3 lentivirus for 6 h, followed by reconstitution in matrigel in 24-well plate. After culturing for 7 days, organoids were further treated with or without 40 μM everolimus for 48 h. Scale bars, 50 μm. I Tumor growth, tumor weights, and photos of PDX3 tumors. Mice were intratumorally injected with shNC or shSF3B3 lentivirus (shSF3B3#1 + shSF3B3#2), followed by oral gavage of vehicle (40%PEG400, 5% Tween-80 and 5% DMSO) or everolimus (5 mg/kg, p.o., every two days for 3 weeks). Data are shown as mean ± SD